There are lots of different types of anabolic steroids , but most of them beefify similarly. When we work out, we create tiny micro-tears in muscle fibers. When the muscle regrows and heals, it grows back a little bit larger, and repeating that process over time is how we get hard and massive (that's the idea anyway). The male sex hormone testosterone facilitates that muscle growth. Anabolic steroids do the same thing but better and faster. They also speed the muscle-healing process by blocking the stress hormone cortisol, which breaks down muscle tissue. That can mean less down time for athletes who go into overtime.
Pregnancy Category C. Corticosteroids have been shown to be teratogenic in many species when given in doses equivalent to the human dose. Animal studies in which corticosteroids have been given to pregnant mice, rats, and rabbits have yielded an increased incidence of cleft palate in the offspring. There are no adequate and well-controlled studies in pregnant women. Corticosteroids should be used during pregnancy only if the potential benefit justifies the potential risk to the fetus. Infants born to mothers who have received corticosteroids during pregnancy should be carefully observed for signs of hypoadrenalism.
Prednisone directly causes atrophy of muscle fibers (myopathy) leading to muscle weakness. This is a very common side effect of chronic (a few months or more) prednisone use but can be either mild or severe. Patients usually notice weakness most in the upper legs. It is not a painful condition directly, but weak muscles and their tendons are more easily strained, which can lead to pain. Muscle weakness that is so severe as to involve the muscles of breathing is rare, but leg weakness can lead to shortness of breath with climbing stairs.